digitalmars.D - varargs for extern (C) vs. extern (D)

I am curious whether there is currently any practical purpose for
std.stdarg vs. std.c.stdarg, as the implementations look identical to
me. Do these both exist just in case something changes at some point,
or are there already situations where both might be needed? Is it
simply that a D program may link against a C library that handles
varargs somehow differently?
Sean

I am curious whether there is currently any practical purpose for
std.stdarg vs. std.c.stdarg, as the implementations look identical to me.
Do these both exist just in case something changes at some point, or are
there already situations where both might be needed? Is it simply that a D
program may link against a C library that handles varargs somehow
differently?

Both are there because one is the official interface to C variadic
functions, and is there for completeness.